.join() Method

Use the .join() method when you want to delimit an array. Delimiters are used as boundaries to separate things. Punctuation marks are commonly used as delimiters. Here's an example:

var meals = ['breakfast', 'lunch', 'dinner'];
console.log(meals.join(' AND '));

Output

breakfast AND lunch AND dinner

See how the word AND is used as a delimiter to separate each of the meals?